A battery balancing system is a technology for adjusting an output voltage of the plurality of battery modules included in a battery system to be the same voltage. When the balancing system is applied to the battery system, it is possible to prevent explosion and fire generated during overcharging and prevent a life of a battery from being decreased due to overdischarging, thereby enabling the battery to fully exert performance.
In general, in order to perform the balancing, a balancing circuit is configured by a method of discharging power of a cell having a high voltage within an application specific integrated circuit (ASIC) to perform balancing on each battery module. However, in the foregoing balancing, the balancing is performed only by the manual method of consuming power of some battery modules, so that there is a problem in that energy of the battery system is not efficiently used.
Korean Patent Application Laid-Open No. 10-2006-0109048 discloses a switching circuit for balancing a battery cell. However, the battery system adopting the foregoing method includes the plurality of switches, so that there is a problem in that a configuration of the circuit is complex, and the balancing can be performed only by the method of manually consuming energy of the battery.